Alpha Labs - Sector 1: Union Aerospace Science Division

Alpha Labs - Sector 1: Union Aerospace Science Division is the fifth level of Doom 3. Built in 2095 and located on Site 2, Alpha is the UAC's center research lab. Sector 1 houses the EPD (Elemental Phase Deconstructor) and the Hydrocon. Maggots are introduced midway through the level in a cutscene.

Summary
Sergeant Kelly radios in again, urging the marine to meet up with Bravo Team as soon as possible. The marine enters the Alpha Labs' reception area and clears out the zombies inside. He then uses a security terminal to open a locked door and proceeds deeper into the facility. He fights his way to the EPD Lab, where he finds that the only way to go further is through the EPD collection chamber. After clearing out the demons and zombies in the EPD control room, he opens a repair gate, giving him access to the collection chamber. The marine crawls into the collection chamber (being sure to avoid the instantly fatal EPD beam) and exits through a maintenance conduit.

The marine heads further through Alpha Labs until he runs into a fire blocking the way. He finds a monitoring station at the EPD particle emulsifier and uses it to extinguish the fire. Upon reaching the EPD contaminant purge room, he encounters a new enemy - maggots. After defeating the maggots the marine crawls through a crawl way underneath the floor and arrives near the section responsible for maintaining the Hydrocon. Eventually, he encounters a survivor, George Krietman, who warns him not to shoot the Hydrocon tanks inside the lab. The marine proceeds further into the base where he uses the PDA of the deceased Bernie Lipsitz to gain access to the Hydrocon itself. Here he catches a glimpse of Counselor Swann and Jack Campbell heading through Hydrocon Observations. The marine finally reaches the exit elevator where he defeats another ambush by maggots before taking the elevator to the next level.

Objectives

 * Alpha Access Elevator.
 * Find the personnel elevator that leads to Alpha Labs Level 2.

Characters

 * Sergeant Kelly
 * UAC announcer
 * George Krietman
 * Elliot Swann
 * Jack Campbell

PDAs

 * Kyle Berger: Found in EPD Lab.
 * Jack Smith: Found in EPD Particle Emulsifier.
 * Bernie Lipsitz: Found in Hydrocon Stabiliazation
 * George Krietman: Obtained by killing George.

Video disks

 * Elemental Phase Deconstructor: In EPD Lab, in the control room.
 * Hydrocon: In Hydrocon Control.

Enemies
Note: includes only enemies that can be fought and killed. The enemy count on Nightmare is the same as on Veteran. There are no changes in the enemy amount in the BFG Edition.

Items
The item count on Nightmare is the same as on Veteran, except the med kits are absent.

There are also three health stations on the level: one with 100 health in reserve, one with 73 health, and another one with 44 health (all of them have 100 health in BFG Edition).

Starting inventory
If the player starts the level via a console command, they will start with these items:

Locker codes
For the sources of the codes, see Doom 3 locker codes.
 * Storage locker #009 - Supplies: 752. Contains: security armor, med kits (large) x2, grenades, clip (large).

Secrets

 * In Hydrocon Junction 1 where the player is attacked by two imps, there's a small semi-hidden control panel on the side of one of the columns which can be used to open the armory in that room.

Trivia

 * On the original Xbox version of the game, the level is divided into two parts: Alpha Labs - Sector 1 East and Alpha Labs - Sector 1 West.
 * If the player fires their weapon at the Hydrocon (even if it wasn't intentional, like a stray shotgun pellet), the entire facility will blow up, killing the marine. The scientist George Krietman warns the marine about this.
 * If the player waits 45 seconds in EPD Lab (the room with EPD beam), an imp will spawn on Marine skill level and above.
 * If the triggers the monster ambush in EPD Particle Scrubber and then backtracks to the previous room, on Marine skill level and above, two additional imps will spawn.
 * The door from EPD Particle Scrubber to EPD Contaminant Purge can be jammed open if a Z-Sec is killed and drops the machinegun in the doorway. After the Maggot introduction cutscene, retreat is still possible through the open door. If the player collects the dropped weapons (by firing a machinegun and reloading) that jammed the door open, the door will close and lock until the necessary maggots are killed. If they're on the other side of the door, game progress is deadlocked without the use of cheats or reloading a prior save.
 * In Alpha Labs Junction, where the player is attacked by multiple maggots, the door normally locks behind the player upon entering the room, and unlocks after the player kills all the maggots, but sometimes the script to unlock the door doesn't work and the door remains closed, preventing the player from going back to replenish ammo/health.